07047: neogeo (whenloading up a multislot system): Next Game and Previous Game buttons won't function. Only one game select button exists.

Description

These two buttons do not respond at all probably because they don't exist on an actual neo geo machine. Instead, there is one "Select Game" button and that button would go straight to the next game (i.e. 1-->2-->3-->4-->1 on a four slot).

Steps To Reproduce

Additional Information

Checked in a wiring diagram of a four slot neo geo manual and no such input like previous game exists.

The next game and previous game buttons function in MAME when a credit or more is registered.

Apparently there's settings in the Bios menu that can change that behavior.

No.15276

Hydreigon

Tester

31 days ago

edited on: 31 days ago

Found that setting in the manual and the previous button works despite no such button's existence officially (I'd call this submission a mistake if it weren't for that). I stated that it isn't present on any official control panel or a wiring diagram in an official manual. The real question is...how was a previous button input found despite it being hidden?

No.15278

Haze

Senior Tester

30 days ago

edited on: 30 days ago

the way this works is one of the differences between the US / non-US systems I believe

use the US bios if you want the behavior you're talking about?

*edit* the forward / back buttons work before inserting a coin with the US bios roms, although there are always both of them, I imagine the cabs with just a 'select game' only had the 'next game' hooked up.

*edit2* the US bios roms with a cyan test grid background appear to allow you to swap before inserting a coin, the other 2 (green / yellow) do not, which is interesting I was wondering why there were different coloured grids on the US sets and not the others, such behavioural changes might be part of it.

No.15279

cuavas

Administrator

30 days ago

edited on: 30 days ago

Neo Geo system boards with MVS edge connectors (i.e. not JAMMA edge connectors) have next/previous game buttons on contacts 26/d. They read in the same bit positions as P1/P2 select on an AES. There's a "soft DIP" setting accessible in service mode to allow game selection during attract mode. Game selection is always possible during the "press start" countdown. Some control panels may have a only a single select button present - if you want this setup, just don't map a key/button to the other select input. MAME is behaving correctly.